Flexographic printing plates are relatively expensive compared to other types of plates such as those used in offset printing; therefore, flexographic printers will only use the appropriate amount of plate material necessary to transfer a graphic image. The graphic image is subsequently transferred to a substrate such as film, paper, or board, etc. Printers reduce the cost of printing when using flexographic plate material, by not using flexographic material where no graphic elements exist.
Corrugated printing is a segment of the industry wherein this practice is common. To keep manufacturing costs as low as possible, the corrugated printer will manually prepare the electronic art in a manner that maximizes material savings, while minimizing the labor cost associated with manually mounting the plates for printing.
This method is accomplished by breaking an electronic art file into smaller pieces called “slugs.” The slugs are then arranged using a software application such as the Kodak TIFF Assembler Plus, to produce an arranged “slugs file.” The arranged slugs file is imaged (or engraved) using a specially designed flexographic imaging device and software, to produce a flexographic plate. The flexographic plate is then cut into smaller plates called “slug plates.” Each “slug plate” represents a slug. The slugs plates are then mounted for printing. The process to prepare a job using this method is described in more detail below.
During the job estimation and quotation phase of the workflow, a job planner or estimator will use an inkjet proof to evaluate which graphic elements are in close proximity to other graphic elements and can therefore grouped together onto a single slug plate. During this process, the planner or estimator is also evaluates the additional labor cost that will be incurred during the plate mounting process by breaking the file and flexographic plate into smaller pieces. Therefore, the quotation for the job reflects the optimal savings in plate material when labor to mount the plates for printing is included.
Following acceptance of the quote, a prepress operator will reference the “marked up” inkjet proof that was used during the quotation process to manually add and position registration marks in and around the elements that will make up individual slug plates. The registration marks aid in re-assembling the artwork during the plate mounting process.
The prepress operator will then output a “mounting die” which is comprised of a CAD-CAM drawing of the container (or package) shape, along with the corresponding registration marks that were placed into the electronic art file. The mounting die is typically a piece of Mylar or film that is manually positioned on an optical/video plate mounting device or pin registration mounting device. The mounting die is used as a guide to properly position the individual slug plates on a “carrier sheet.”
Following output of the mounting die, the electronic art is output to a TIFF bitmap format and checked for accuracy. Following approval, the composite file is then broken into individual slug files for imaging. This is accomplished by breaking an electronic art file into smaller pieces called slugs, and the slug plates are arranged using a software application such as the Kodak TIFF Assembler Plus, and the resulting output file is imaged to a flexographic plate. The flexographic printing plate, using current technologies is imaged (or engraved) using a specially designed flexographic imaging device and software.
After the plates have been processed via solvent or thermal processing to create a relief image, dried, and cut to size, the slug plates are manually positioned on a “carrier or mount” using double sided sticky back tape and edge sealant. After each plate has been mounted and the edge sealed, ink is applied manually using a rubber roller and an impression of the mounted plates is made on the “mounting die.” This process creates a “mounters proof” or actual representation of what will be printed on press. The “carriers or mounts” are then used in a corrugated printing press to produce the finished container or point of purchase display.
Although the current workflow described above has numerous benefits, it also has two major deficiencies. Because the original composite file or film was broken into smaller pieces, correction cycles are not easily accommodated because the composite file is no longer available for reference (for position) when placing new graphics or re-mounting worn individual slug plates. Also, there is no ability to save the job estimate information as a template to be used during production. Thus eliminating subjective decision, which will ensure that job costs are in alignment with the estimate/quote that is made at the beginning of the workflow.
In the process, prior art determining of the optimum number of slug plates versus the labor costs to mount the job is subjective. There is no embedded pricing information or analysis available to assist in the process, i.e. real time cost analysis as the work is performed.
A prior art method is described in U.S. Pat. No. 6,954,291 (Klein et al.). Klein et al. discloses reading a previously prepared output ready file such as TIFF bitmap, and automatically scanning for slug plates. The scanned slug plates are cut and pasted into a new file while minimizing the possible waste in the created new file. U.S. Pat. No. 6,954,291 does not suggest any embedded cost calculation to be reflected by the chosen geometry of the new file.